(a) Field of the Invention
The present invention relates to thin film transistor array panels for liquid crystal displays (referred as LCDs hereinafter).
(b) Description of the Related Art
One of outstanding displays is a thin film transistor liquid crystal display (referred as LCD hereinafter), and it is important to reduce a manufacturing cost and to improve a image quality.
To reduce the cost, the manufacturing process needs to be simple. One of the way is to reduce the number of masks which are used in the process.
Meanwhile, one of important factors which affect to the image quality of the TFT LCD is an aperture ratio. In other word, the more the aperture ratio is large, the more the image is bright and clear. The number of the pixels needs to be increased to realize high resolution image, but the aperture ratio is decreased when the display is fixed, since the widths of metal wires and the size of a thin film transistor are limited.
Generally, in a conventional liquid crystal display, the portion outside pixel electrodes is covered with a black matrix which is formed on one of two panels of the LCD.
However the step in which an additional mask is used to form the black matrix is required, and the consideration of the alignment margin causes to be decreased.